/**
 * @param {string} s
 * @return {string}
 * @description 暴力
 */

var replaceSpace = function (s) {
    s = s.split("")
    let len = s.length
    for (let i = 0; i < len; i++) {
        if (s[i] === " ") {
            s[i] = "%20"
        }
    }
    s = s.join("")
    return s
};
replaceSpace("We are happy.")